Efficacy and safety of citrate-based anticoagulation compared to heparin in patients with acute kidney injury requiring continuous renal replacement therapy: a randomized controlled trial

INTRODUCTION A systemic anticoagulation is often required to prevent circuit and filter clotting in ICU patients undergoing continuous renal replacement therapy (CRRT). A regional citrate-based anticoagulation (RCA) does not induce a systemic anticoagulation and prolongs the filter lifespan, but metabolic side-effects have been associated with this therapy. We conducted a randomized controlled trial with patients requiring CRRT to determine whether RCA using a balanced predilution replacement fluid is more effective than heparin in terms of renal replacement delivered dose and safety profile. METHODS One hundred and three patients with AKI requiring CRRT were included. The patients were randomized to either CRRT with RCA or heparin anticoagulation. Primary endpoints were effective daily delivered RRT dose during the first 3 days of CRRT and filter lifespan. Secondary endpoints were 28-day and 90-day survival and severe metabolic complications and bleeding disorders. RESULTS Median CRRT duration was 3.0 (2-6) days. Effective delivered daily RRT doses were 29 ± 3 and 27 ± 5 mL/kg/hr in the RCA and heparin groups, respectively (p = 0.005). Filter lifespans were 49 ± 29 versus 28 ± 23 hrs in the RCA and heparin groups (p = 0.004). Survival rates at 28 and 90 days were 80-74% in the RCA and 74-73% in the heparin group. Electrolytes and acid-base disturbances were uncommon and transient in patients treated with RCA. CONCLUSIONS These results show that RCA is superior to heparin-based anticoagulation in terms of delivered RRT dose and filter life span and is a safe and feasible method. This does not translate into an improvement in short term survival. TRIAL REGISTRATION ClinicalTrials.gov NCT01269112 . Registered 3rd January 2011.